Deprecate it as well, because hey, it's redundant now.

src/main/java/net/minecraftforge/fml/common/FMLCommonHandler.java

@@ -135,8 +135,10 @@ public class FMLCommonHandler
     /**
      * The FML event bus. Subscribe here for FML related events
      *
+     * @Deprecated Use {@link MinecraftForge#EVENT_BUS} they're the same thing now
      * @return the event bus
      */
+    @Deprecated
     public EventBus bus()
     {
         return eventBus;